Old 12-24-2013, 04:33 AM
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Join Date: Sep 2007
Location: Moore Oklahoma
Posts: 129

This is what I found on the Holley website, contained in their Dominator instructions.

Inclusion of this circuit was required as a means of obtaining a smooth transition from the idle to the main metering system. It is intended to overcome a dip in the fuel delivery curve of the Model 4500 carburetor. Increasing/decreasing restrictor size delivers more/less fuel to enrich/lean the mixture for transition.
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